Rotary disk brush



Jan. 23, I951 c. N. SMITH, JR 2539,211

ROTARY DISK BRUSH Filed Feb. 12, 1949 -3 x l) \KSII/ /9 2 INVENTOR.

2 Couri/ana N Smff/gJr ATTORNEYS Patented Jan. 23, 1951 UNITED "S TATESPATENT OFF ICE 7 ROTARY DISK'BRUSH 1Courtland.N. Smith, Jr., Glen Ridge,N.-J., sas- Signor to .The Begina Corporation, 'Rahway,

N.-J., a corporation of New York Application February '12, 1949, SerialN0."7.6;l69

The :invention "relates to rotary brushes .for sweeping: scouring,iandgpolishing floors and like surfaces.

Thegeneral "object of the invention is to provide a new, simple,inexpensive and practical rotary brush .which may be operated with aminimum of vibration and-noise, which embodies an improved distribution:of bristle tufts, and which is of light weight and highlyresistant toWater, detergents, :and other common cleaning agents.

.A special object -,is to provide :a rotary brush of the classdescribed, the 'base, or bristle-holding back, of which .is :a singlecasting, preferably made of injection molded .ethyl cellulose or ofanother plastic which is .of relatively-light weight, highly impervious"to water and detergents, and of v.poor sound conductivity, and havingformed therein on one face a novel distribution of bristle socketsadapted to hold .a plurality of tufts zthe ends-of which'are moreuniformly distributed'over ananmilanbrushing surface. Poor soundconductivity-isdesirable for the purpose of minimizing operational noiseupon incidental contact of the base and ,a floor, baseboard, or otherobject. Imperviousnessto water and detergentsis a manifest advantagaaasit is well known in the artthat wooden bases i0! rotary brushes of thisclass are highly subject tozslightzchanges of size and shape due toabsorption ofcleaning agents and variations of moisture content and inconsequence often become permanently Warped and operate with increasedvibration and noise.

A further object of the invention is =to; provide a brush-of theclassdescribed the base of which is provided with bristle :socketsarranged as :a pluralityaof circularseriesihaving acommon center, thosesockets in series nearer said :center being of circular cross-section.and having axes normalto the plate of the baseiandthosesockets inseries fartherfrom saidcenter being'of rectangular cross-section andhaving the :shape of truncated wedges so :that .tufts f :bristles heldwithin said: last named sockets, and :conseguently near the periphery ofthe brush, are so close together as :to :provide what is substantiallysan annular Ltuft of evenibristle incidence, .with ithose bristlesnearest "the-:center .of the brush being more :nearly .normal :to theplane .of the base and those .i'bristles ifarthest therefrom libeing 1less normal to said:planelandsextending:centrifugally.

.In 1 the drawing:

. Fig. 1v is aside :-view;.zFig. :2 is.;a1itop .view, and Fig. .3 is a:bottom viewgof :thebrushcof tithe pres-- ent: inventiomieach figurebeing "incomplete awith =8 Claims. (01.15-480) respect to the bristles.Only a few bristlesare shown in each figure; but the .:general shape ofthe tuft arrangementisindicated by dotted lines; andy-in Fig. :3, twozormore tufts of bristles .are shown in each concentric series ofbristle socketsin lone generaLangular-area so thatthe structure of thecomplete brushing surface and the advantages of athelnovel form ofsocket arrangement may-be 'fullyunderstood. In Fig. ,3, only a portionof the bristlesockets are shown, but the distribution pattern "of the.entire base is .a repetition of *the series illustrated.

Fig. 4 is .a fragmentary-sectional view of the base of the brush in{accordance with the index 44'of.-Fi g.i 3. Here no bristles are shown.

.The base, or bristle-holdingback, of the brush isdesignatediniitszentirety l0. Thismemberis a discoid Ehaving -a;p1anelower surface II with a countersinktherein at 1-2 which is. of circularshape-.andwconcentric with :the base, and having a3central perforationat=l3 to accommodate .a hub :adapted .to :accommodate :a shaft '(notshown) llfOI' rotatingitheibrush. Therbase ibis provided with 'a hub 14(preferably metallic) which .is :castellate'd at 1 5, 15, ,15, .15., toprovide keyways for :a .suitable :member :mounted upon said :shaft :toengage and impart rotary motion tozthe-brush. The bore I16 of .thezhubldxisiexpanded at 16a .to :facilitate the entry of .a shaft into :saidbore.

The underside :of the .base 10 provided with .a aplurality-:her.e,:inlFig. 3, with four-of circularly disposedand concentric series ofbristle sockets, the innermost and 'THBXtXSBI'iGS being of sockets *of=circular cross-section and axially normalflto the'plane'ofthebase (i.,e., to the sur- .face 1.!) pandthe outermostand next series be ing ofsockets of rectangular crossesection and shaped like truncatedwedgeszmore particularly described below. See.Figs..-;3 and 4. Any sock-.et of lithe innermostrseries isindexed #8; any socket of its adjacentseries, l 9. :Sockets [8 and 11:9:may rbe of the: same .-shape and size,and .are preferably :of simple cylindrical form, although .a slighttaper :so as to expand the sockets at their; mouths may be 1 introducedfor the purpose of facilitating separation of dies :in injectionmolding'operation; :here, .in .--Fig. 3, sockets -IB .and I9 areshowntobe .arrangedin sta ered angular relationship .;to;;each other..-Any socket of vthe outermost-"series :is indexed .320; any socket:of;.itszadjacentz seriesgll .Sockets z I33 and :i-9 2 are allioftheishapebfvtruncated wedges; ;,but sockets .zflcarerpreferably largerthan sockets 2| ,to compensate ifor :the greater centriiugal "distanceof the former with respect to the latter and to insure a more uniformincidence of bristles over the peripheral brushing surface.

That surface of any socket 20 or 2! nearest to the center of the brushis designated 22 and is substantiall normal to the surface H, or general bottom of the base ii). That surface of any socket 23 or 2|farthest from the center of the brush is designated 23 and is inclinedwith respect to the surface i 5 so that the mouth of any socket 26 or 2iis larger than the bottom thereof.

The sockets 2G and 25, each kind in its series, are separated by narrowsepta so that the bristles may be as close together as desiredthroughout the peripheral series of tufts as a whole. Those septabetween sockets to within the related series are designated 2d, andthose between the sockets 2i are designated 25. See Fig. 3.

The purpose of forming the sockets of the peripheral seriessubstantially in the shape of truncated wedges is of course obvious (andis clearly illustrated in Fig 3): provision is made for mounting bristletufts so as to form a practically uniform annularbrushing means. Areasof the brushing surface near the periphery of the brush having aconsiderably reduced incidence of bristle ends are thereby avoided. Anapproximation of rectangular cross-section for the sockets of the outerseries is sufficient for practical purposes. It will be evident that theouter bristle sockets may be of truly rectangular crosssection and theseparating septa of rhomboid crosssection; that the outer sockets may beof rhomboid cross-section and the septa of rectangular section; and thatthe radial surfaces of the sockets normal to surface H of the base maybe planes and the near and distant sides of the sockets with respect tothe center of the brush, may be cylindrical. The gist of the pat-. ternof the peripheral series is that of a closely positioned assembly ofsockets of truncatedwedge-shape having substantially quadrilateralcross-section greater at the mouth than at the bottom, it beingimmaterial for the purposes of the present invention that thecentripetal and centrifugal sides of the sockets are planar orcylindrical to accord with the discoid formation of the base it, so thateach tuft of bristles may be mounted, and also may be formed by thesocket in which it is received, so as to have a roughly quadrilateralcross-section to the end that adjacent tufts are so close together as topresent the appearance of a single annular tuft of uniform bristleincidence.

Fig. 3 shows, mounted on two shoulders 26 and 21 provided within thecountersink at l2 within the base it! and secured by means of two capscrews 28 and 29 a bearing structure 3| aligned with the perforation atl3. This structure, usual in the art, provides means for aligning aferrule or the like on the bottom of a shaft provided for rotating thebrush.

In Fig. 3, tufts of bristles are shown mounted in several of the socketsof the base if). The bristles, generally are indexed 32 in Figs. 1 and2, wherein only a few are shown. These few shown in these figures and inFig. 3, together with the dotted margin lines of the three figures,clearly indicate the general disposition of the bristles in theaggregate with respect to the base 10. In Fig. 3, two tufts 33, 33 areshown mounted in adjacent sockets l8, l8 (obscured) of the innermostseries of sockets; adjacent thereto two other tufts 34, 34 are shownmounted in adjacent sockets l9. l9 (obscured) of the next series;adjacent to these last mentioned tufts three other tufts 35, 35, 35 areshown mounted in consecutive sockets 2|, 2|, 2| (obscured) of the nextbut outermost series; and adjacent to tufts 35 two further tufts 3B, 36are shown mounted in adjacent sockets 20, 2f) (obscured) of theoutermost series. The nine tufts shown occupy a more or less commonangularposition with respect to the base It) for the purpose ofillustrating thereby the general pattern of the bristle ends at thebrushing surface of the device.

It will be noted that tufts 33, 33 and 34, 34 are of the ordinaryroughly circular cross-section type and are set in staggered formationin the common manner. This arrangement of tufts is satisfactory for theinner part of the brushing surface. However, near the periphery it isdesirable that the high incidence of bristle ends be preserved and forthis reason sockets and tufts of roughly quadrilateral cross-section areprovided, and Fig. 3 shows how the incidence of bristle ends is therebymaintained in substantial uniformity over the entire annular brushingsurface. This arrangement of bristle ends provides a brush having agreater sweeping, brushing and polishing efficiency than that of a brushwhose bristles are arranged so as to have a decreasing incidence of endsin accordance with the radial distance from the brush center.

It will be understood that in making the base it) by molding the same,one operation suffices to form the entire brush back with the socketsfor the bristles complete in such operation, and avoids the turning anddrilling operations necessary in preparing wooden brush backs. Also in amolded base of the kind described the edges of the bristle sockets arenot sharp and interfere less with the operation of inserting the varioustufts. In the base H), it will be understood that a simple two-part diemay be employed in injectioir-molding the same as the configuration ofthe sockets and other parts of the base are such that a simple two-partdie may be separated by movement along a common axis (note that a socket213, for example, in Fig. 4, which is generally like a socket 2|, isshaped so that the male portion of a die part employed to form thesocket may be withdrawn along a direction parallel to the axis of thebase itself).

I claim:

1. A rotary brush having a brushing surface substantially normal to theaxis of rotation of said brush, comprising a discoid base, having aplurality of concentric series of sockets therein, bristles securedwithin said sockets, said bristles forming a substantially planarbrushing surface, one series of sockets, near the periphery of saidbase, being substantially quadrilateral in crosssection in a planeparallel to said brushing surface, and a second series of socketsadjacent to said first-mentioned series, also substantiallyquadrilateral in cross-section in a plane parallel to said brushingsurface, and staggered angularly relative to said first-mentionedseries.

2. A rotary brush having a brushing surface substantially normal to theaxis of rotation of said brush comprisin a discoid base, said base beingcomposed of a moldable material and having a plurality of concentricseries of sockets therein, bristles secured within said sockets, saidbristles forming a substantially planar brushing surface, one series ofsockets near the periphery of said base, being substantiallyquadrilateral in cross-section in a plane parallel to said brushingsurface, and a second series of sockets adjacent to said first-mentionedseries, also substantially quadrilateral in cross-section in a planeparallel to said brushing surface, and separated from saidfirst-mentioned series only by a thin wall of said moldable material.

3. A rotary brush having a brushing surface substantially normal to theaxis of rotation of said brush comprising a discoid base, having aplurality of sockets therein, a series of said sockets near theperipheral edge of said base being arranged in a circle about the axisof rotation, a second series of said sockets being arranged 'in asmaller circle adjacent to and concentric with said first-mentionedseries, the first-mentioned series of sockets having the edges at themouths thereof which are adjacent to said second-mentioned series ofsockets forming substantially straight lines and said second-mentionedseries of sockets havin the edges at the mouths thereof which areadjacent to said first-mentioned series of sockets forming substantiallystraight lines, and said last-mentioned edges being substantiallyparallel to said first-mentioned edges.

4. A rotary brush as claimed in claim 1 wherein said series of socketsof substantially quadrilateral cross-section are the series nearest theouter periphery of said base.

5. A rotary brush having a brushing surface substantially normal to theaxis of rotation of said brush comprising a base having a plurality ofsockets therein, bristles secured within said sockets, said bristlesforming a substantially planar brushing surface, a series of saidsockets near the peripheral edge of said base positioned in a circle,the edges at the mouths of said series of sockets forming substantiallystraight lines and adjacent edges of adjacent sockets of said seriesbeing substantially parallel, a second series of sockets adjacent tosaid first-mentioned series of sockets and positioned in a circlesmaller than and concentric with said first-mentioned series of sockets,the edges of said second-mentioned series of sockets at the mouths ofsaid second-mentioned series of sockets forming substantially straightlines, said first-mentioned series of sockets having those edges of saidfirst-mentioned edges which are furthest from the outer peripheral edgeof said brush substantially parallel to the adjacent edges of saidsecond-mentioned series of sockets.

6. A cylindrical rotary brush as claimed in claim 5 wherein saidsecond-mentioned series of sockets are staggered angularly relative tosaid first-mentioned series of sockets.

7. A rotary brush having a brushing surface substantially normal to theaxis of rotation of said brush, comprising a discoid base having aplurality of sockets therein, bristles secured within said sockets, saidbristles forming a substantially planar brushing surface, the socketsnearest the outer peripheral edge of said brush being substantiallyquadrilateral in cross-section in a plane parallel to said brushingsurface and said last-mentioned sockets having the side walls nearestthe outer peripheral edge of said brush disposed so that the edges ofsaid side walls at the mouths of the said last-mentioned sockets arenearer the outer peripheral edge of said brush than the edges of saidside walls at the bases of said last-mentioned sockets, and saidlast-mentioned sockets having the walls furthest from the peripheraledge of the brush disposed so that the edges of said last-mentionedwalls at the mouth of said last-mentioned sockets are substantially thesame distance from the outer peripheral edge of said brush as the edgesof said last-mentioned walls at the base of said last-mentioned sockets.

8. A rotary brush as claimed in claim 7 in which the sockets adjacent tosaid sockets near est the outer peripheral edge of said brush are shapedsimilarly to said sockets nearest the outer peripheral edge of saidbrush.

COURTLAND N. SMITH, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,009,335 Olson Nov. 21, 19111,452,307 Martin Apr. 17, 1923 1,792,363 Dehufi Feb. 10, 1931 1,950,379Angell Mar. 13, 1934 2,156,514 Sassano May 2, 1939 2,295,687 PonselleSept. 15, 1942 2,306,389 Jorgensen Dec. 29, 1942 2,355,744 Myers Aug.15, 1944 2,397,471 Cox Apr. 2, 1946 2,398,570 Wildhaber Apr. 16, 1946

